Canker Sores vs Ulcers

Instructor: Justine Fritzel

Justine has been a Registered Nurse for 10 years and has a Bachelor's of Science in Nursing degree.

Most people are very familiar with the discomfort of a canker sore in their mouth. In this lesson we will explore the similarities and differences between canker sores and cold sores.

Canker Sores and Other Oral Ulcers

It starts with a tender spot in your mouth. You can feel it on your inner, lower lip. You use your tongue to prod it and you feel a small bump. You go to the bathroom mirror and pull your lip down to find a small ulceration known as a canker sore.

Canker sores
canker sore

The term ulcer simply means a lesion in which the skin or mucous membrane is deteriorating. There is a wide variety of different types of ulcers. We will be discussing oral ulcers in this lesson. The two most common mouth sores are canker sores and cold sores, which we will explore in this lesson.

Canker Sores

Apthous stomatitis is more commonly known as a canker sore. A canker sore is white or yellow in color with a red border. These occur inside the mouth, usually on the lips, cheeks, or top of the mouth. They can occur on the tongue and the throat as well. A person may feel tingling or a mild pain and itching sensation before the ulcer appears. They cause pain and heal on their own, but oftentimes will recur.

Often, more than one canker sore will appear simultaneously and they may group together in a cluster. These small ulcers are painful and sensitive to touch, but luckily they are not contagious! Canker sores are more common in women than in men and approximately 20% of Americans experience recurring canker sores. Ouch!

The cause of canker sores is not clear. It is believed that they may result from an immune reaction, trauma, stress, hormones, food allergies, or nutritional deficiencies.

Since canker sores heal on their own in one to two weeks, no treatment is necessary. But because canker sores are painful, people experiencing these sores should avoid spicy or acidic foods and might want to use an over-the-counter pain reliever until the sores heal.

Canker sores are often confused with cold sores. It is important to differentiate which type a person is experiencing, as these two types of sores are very different. Let's now learn about cold sores.

Cold Sores

Cold sores usually occur near the mouth or other areas of the face. Rarely, they may appear on fingers, nose, or inside the mouth. A person will usually feel a tingling or burning sensation before the sore actually appears. Cold sores are red, fluid-filled blisters that appear in clumps and can last for two weeks or longer. Cold sores can be painful and very tender to touch.

A cold sore

Cold sores are caused by a virus called herpes simplex. There are two types of herpes simplex viruses (Type 1 and Type 2). Type 1 herpes causes cold sores. These are contagious and can be spread through close contact such as kissing. The virus can also be spread from sharing food, drinks, or personal items such as a toothbrush or razor. Even before the sores are visible, they are contagious and remain contagious until the sore crusts over. A person may also experience symptoms such as fever, muscle aches, and swollen lymph nodes during an outbreak.

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